Carburetor with stationary metering pin



Aug. 9, 1955 A. c. RUSSELL CARBURETOR WITH STATIONARY METERING PIN Filed Oct. 18, 1952 llll Awdren/ 6m@ Fae United States Patent O CARBURETOR WITH STATIONARY METERING PIN Andrew Craig Russell, Shawnee, Okla. Application October 18, 1952, Serial No. 315,542 1 Claim. (Cl. 261-50) This invention relates to carburetors particularly adapted for use with internal combustion engines to admix air and fuel, such as gasoline, atomize the latter and direct the admixture to the engine, the primary object being to improve upon the carburetor forming the subject matter of my co-pending application, Serial No. 41,933, led August 2, 1948, now Patent No. 2,614,581, this being a continuation-in-part thereof.

In my said co-pending application, as well as in my related Patents 2,366,056; 2,506,812; 2,529,665; and 2,536,700, carburetors are provided which have a metering pin reciprocable within a stationary bore and operably coupled with an air valve for reciprocation thereby as the air valve in turn moves through arvertical, rectilinear path of travel. In said application and said patents, as well as in my Patent No. 2,536,889, the vertically reciprocable air valve is mounted on a stationary tube for reciprocation with respect thereto.

It has been found that such principles can be improved upon to a great advantage by eliminating chatter and dancing of the metering pin as a consequence primarily of vibration and shaking as the automobile, with which the carburetor is used, passes over rough terrain.

It is the primary object of the present invention therefore, to provide a carburetor having a stationary metering pin within the fuel bowl thereof, together with a tube through which the fuel-air admixture passes, fttable over the metering pin and reciprocable with respect thereto whereby to admit varied quantities of fuel in direct proportion to the requirements of the internal combustion engine.

Another object hereof is to provide a carburetor as above set forth that includes a vertically reciprocable air valve as above mentioned which is directly connected with the reciprocable tube for reciprocating the latter and thereby admit progressively greater amounts of fuel to the tube as the air valve rises to admit additional air in response to changing pressures within the intake manifold of the internal combustion engine.

Other objects include important details of construction, all of which will be made clear as the following specication progresses, reference being had to the accompanying drawing, wherein:

Figure l is a substantially central, cross-sectional view taken through a carburetor having a stationary metering pin made pursuant to my present invention; and

Fig. 2 is a fragmentary, cross-sectional view taken on line II-II of Fig. 1.

Reference may be had to my prior patents above identied and particularly to Patent No. 2,366,056, for a complete understanding of the basic principles of operation of a carburetor such as forms the subject matter hereof.

As in my aforementioned prior disclosures, there is provided a hollow housing broadly designated by the numeral 10, having an air inlet opening 12, an outlet 14 to the intake manifold not shown, of an internal combustion engine and a continuous passage therethrough ICC interconnecting the inlet 12 and the outlet 14 and broadly designated by the numeral 16.

A fuel bowl 18 is removably mounted on the bottom wall 20 of housing 10 and is placed in communication with a source of raw fuel such as gasoline, not shown, by a line 22, having a valve 24 therein that is in turn controlled by a float 26 within the fuel bowl 18.

A tubular member 28 has a pair of spaced, outturned flanges 30 and 32 within the fuel bowl 18, the former 0 being in underlying engagement with the bottom wall 20 and secured thereto in any suitable manner such as by bolts 34. The member 28 has a continuous, vertical bore 36 therethrough placing the fuel bowl 18 into communication with the passage 16. A length 38 of reduced diameter forming an integral part of the member 28 extends upwardly through an opening 40 in the wall 20 and is provided with external threads 42 within the passage 16. A nut 44 on the threaded length 38, cooperates with a ring-like air valve 46 which it is adapted to support in closing the passage 16 when the valve 46 is resting on the nut 44 as shown in the drawing. The nut 44 is rotated and therefore, raised and lowered toward and away from the bottom wall 20 by means of a pin 48 having a worm 50 in mesh with external threads 52 on the nut 44. The bore 36 of member 28 is placed in communication with the passage 16 by a plurality of downwardly and inwardly inclined passages 54, the nut 44 having a cavity 56 for clearing the uppermost ends of the passages 54.

A plurality of rods 58 passing through the ybottom wall 20 and the flanges 30 and 32 for reciprocable movement therein, are joined at the lowermost ends thereof by plate 60 within the fuel bowl 18, and are connected to the valve 46 at their uppermost endls. An opening 62 in the plate 60 clears a vertically reciprocable tube 64 within the bore 36 terminating at its` lowermost end within the fuel bowl 18 and at its uppermost end above the valve 46 and below the outlet opening 14.

A rigid, tapered metering pin 66 secured directly to the bottom wall of the fuel bowl 18 and extending upwardly therefrom, projects into the tube 64 at the lowermost end of the latter. The tube 64 is provided with a wall 68 therewithin that may be either integral therewith or in the form of a press-fit plug disposed above the uppermost end of the pin 66 and having a vertical perforation 70. Additionally, tube 64 has an elongated, vertical slot 72 immediately above the wall 68 in register with each inclined passage 54 respectively, which slots 72 and passages 54 remain in registration at all times during reciprocable movement of the tube 64. Tube 64 is secured directly to the valve 46 for reciprocatiou thereby through the medium of a cross plate 74 secured to the valve 46 and to the tube 64. A choke Valve 76 is provided in the passage 16 adjacent the inlet opening 12 and an auxiliary valve 78 normally spring-loaded to the closed position shown in Fig. l is adapted to admit air into the passage 16 when valve 76 is closed in response to decreased pressure within the passage 16 between the valves 76 and the outlet opening 14.

It is seen that air is admitted from the passage 16 into the tube 64 by way of passages 54 and slots 72 to impinge upon the level of liquid fuel within the tube 64 above the wall 68. Reduced pressure at the uppermost end of the tube 64 as a result of suction created by the intake manifold of the internal combustion engine, moves the air and fuel admixture upwardly from the wall 68 through the tube 64 and through the outlet opening 14 to the engine. More or less fuel .is admitted to the tube 64 and more or less air flows through the passage 16 as the extent of suction by the intake manifold varies, since increased suction reduces the pressure above the inlet 12'to outlet 14` and simultaneously l'permits'more I raw fuellin the fuel bowl 18to enter the ,tube-64 around the metering pin 66;" Raising Yand lowering of the nut 44 by manipulationrof pin' 48', providesy adjustment fory idling purposes in the Ysamernanner as fully described in my aforementioned patents.

It is now seen that for the rst time there is'provided a vertically.reciprocableg tube 64 that cooperatesAA with'a stationary pin4 66,"which`tube 64'isv motivated simulr" taneously with'the valve 46and`by, the latter because of `the direct connection between tube. 64 andthe tvalve 46` throughthe plate 76:, Tests. have proved that these.

improvements which eliminate vchattering `and jfdancing ofthe pin 66 withinV the fuel bowlf18,"obviate any tend?. ency to constantly flood the engine with jets ofV raw Afuel as is the tendencywhenthe metering lvalve islloatingly mounted or permitted to reciprocate. as inA my aforesaid disclosures. Elimination of thebursts of unneeded rraw fuel as a consequence of movement of `a vehicle with which the carburetor is used, provides for smoother operation and reduces gas consumption,L andwhi1e changes may be made from the details'` of construction hereinabove described, it is'desired to be limited only by the spirit of the invention as denedjby the scope of;v

the appended claim.

Having thus describedthe invention what isclaimed as new and desired to be secured by Letters Patent is In a carburetor; a housing having an air inlet, anv

outlet, and a passage therethrough, said passage including an intermediate, circular aperture having a verticalaxis; a hollow fuel bowl mounted on said housing and therebelow, said bowl vertically underlying -said aperture of the passage; a plurality of elongated, vertical rodsjmount` edwin the housing for vertical reciprocation relative thereto, the lowermost ends of saidv rods beingfdisposed within said bowl and the uppermost ends thereof being disposed within said `passageand adapted -topass-through said aperture when they are vertically reciprocated; valvesupporting structure of circular cross-section mounted on the housing beneath and in axial alignment with said aperture, said structure extending upwardly to said aperture to define an annular ope ning between the housing and the uppermost extremity of the structure, said struct ture being providedg with a vertical :bore therethrough and a lateral passage `communicating .with said inlet and with said bore .intermediate the extremities, ofthe latter; an annular valve within the passage and above said structure, saidgvalyebeillgnscured to the uppermost-t'` ends Aof the rods and thereby rnpuntedfor vertical reciprocation to and from a seated positionresting on said structure and closing said opening; an elongated tube slidably mounted in said bore for vertical reciprocation, the uppermost extremity of the tube extending above the structure and throughs the valve into communication with said outlet, ,the klowermost end of the tube extending through,v the structurev andthe housing into the, bowl, `saidltubneV` being provided withanrelongated, 'vertical slot in, corn-lv munication with" said lateral passage regardless of Vthe ,l reciprocatedposition of nthe tubeya plate interconnecting` the lowermost ends of the rods withinV the bowl andprovided with an openingrlearing the tube; a 4crossfplate Withinl the. Passage md vabove..the.aperture interconneting., the tube with "the valve; and an upright, tapered,'meter; ingvpin rigidlyvmountedn the bowl kand Aextendingup-` wardly 'therewithin into a lowermost portion of said tubef I Referencesf'Citedin thele of thispatent UNITEDSTAIES PATENTS 1,064,867.: Stewartfense-, Junev17, 1913 1,213,209 Kirby, .Tan'.v23', 1917 1,493,567- Raytieldg..A l May ,13, 1924 1,493,975 Folberthfet all May ,'13,` 1924 2,091,273 t Crippen` 1 Aug..,31,19,3,7- 2,366,056. Russellt. V Dec.v26, 1944s 

